Peace of mind during the day can start with a good night’s rest, according to WashU sleep expert Rebecca Cox.
We all know the feeling. After a long day of worrying about looming deadlines and stacked to-do lists, it can be hard to fall asleep. But the connection between anxiety and sleep goes deeper than most people realize, said Rebecca Cox, assistant professor of psychological and brain sciences.
Cox, who joined WashU in Fall 2024, has built her career studying the intersection of sleep and mental health. Through sleep diaries, interviews, and data collected from wearable devices, she has worked to untangle the complicated push and pull that can deeply affect a person’s quality of life.
Her research has uncovered an important trend: Poor sleep is a major cause of anxiety. Perhaps surprisingly, the two-way street that connects sleep and anxiety mainly runs in one direction. “We have found that people are more likely to feel anxious if they haven’t slept well,” she said. “But being anxious during the day has a relatively weaker impact on subsequent sleep.”
The good news is that a shortfall of sleep is usually a fixable problem. “Good sleep can be therapeutic for people with anxiety,” Cox said.
Cox is particularly interested in college students and other young adults, a group that often reaps the consequences of putting sleep far down on their list of priorities. “At a university, there can be a culture of busyness, stress, and putting work and productivity over personal health,” she said. “Young adulthood is also a time when we see a lot of new anxiety disorders. Getting enough sleep can be a huge help.”
Even students who don’t struggle with anxiety should be motivated to get enough sleep. “We know that sleep loss interferes with learning and memory,” Cox said. “Staying up late to cram for an exam is actually counterproductive.”
There’s more to a good night’s rest than simply putting in the hours. As Cox reported in a 2020 review article, sleep continuity, or staying asleep for long stretches, is especially important for peace of mind.
For college students or anyone else who has trouble falling asleep and staying asleep, Cox has some scientifically supported advice. First, keep a reliable sleep schedule and avoid naps. If you find yourself tossing and turning, she recommends getting out of bed and doing something relaxing until you feel sleepy. “The idea is that you don’t want to associate the bed with wakefulness,” she said. “You can relearn that the bed is for sleep.”
Maintaining healthy light exposure is important too. That means exposing yourself to bright lights in the morning but keeping things dim at bedtime. Bright lights at night can throw off a person’s natural circadian rhythms and make it harder to fall asleep. The light from a phone by itself probably isn’t as disruptive as a high-wattage overhead bulb, but Cox explained that doomscrolling on social media right before bed isn’t exactly a recipe for sound sleep.
Above all, Cox said, people of any age need to make sleep a priority for the sake of their mental health as well as their overall productivity and energy levels. A good night’s sleep should be nothing to worry over.
